Six out of ten voters in California now believe same-sex marriage should be legal, according to a recent poll conducted by the University of Southern California and the Los Angeles Times.

The poll, which surveyed California’s registered voters, found that only 36% of respondents were against marriage equality, with 58% in favor. In 2010, the same poll found that 52% of Californians favored same-sex marriage, compared with 40% against. Thus, within three years, the margin between those for and against equal marriage rights has increased from 12 to 22 points.

The poll also found that younger voters were far more likely to support marriage equality. Voters ages 19 to 29 were 76% in favor, compared to 52% of voters ages 50 to 64. There was also a significant spread between the sexes. At 63%, women in California were more likely than men, at 52%, to endorse same-sex marriage.

Nationwide, 51% of Americans are in favor of equal marriage rights, making California’s approval seven points higher than the national average. At 58%, it also has one of the highest state approval percentages in the country. The current figure is a significant difference from the vote on Proposition 8, in which 52% of California voters approved a constitutional ban on same-sex marriage in 2008. The poll arrives on the eve of a decision by the nine justices of the Supreme Court on whether or not to overturn the controversial state constitutional amendment.

"There has been movement across the board," Dave Kanevsky, research director of the polling firm American Viewpoint, told the Times about the issue of same-sex marriage. "Every group has moved."